CAREER: Tailoring Photo-Switchable Interfaces using Functional Polymer Brushes

技术概述：该提案概述了一个5年计划，重点是了解表面结合聚合物刷的光诱导构象变化如何影响光致变色薄膜的表面、界面和宏观性能。在延伸的聚合物链中，光致变色基团的三维排列导致表面官能团的密度增加，这可以用来扩大功能涂层的刺激响应性质。本课题旨在利用表面引发聚合技术合成光致变色聚合物刷，可完成以下三个研究目标：(1)利用光通过金属离子络合控制光致变色聚合物的比色响应。将阐明含螺吡喃聚合物在不同金属离子存在下辐照时光诱导络合的可逆结合机制，并利用该机制制备可逆离子传感器。(2)研究可逆的、光切换的粘附。经过光诱导相分离的表面设计将允许表面从粘合状态切换到非粘合状态。(3)在单分子水平上研究光致机械运动。利用光诱导不同自由能表面上的随机线圈和延伸链之间的构象变化，导致光致机械运动。非技术总结：利用光作为外部刺激，创造具有控制界面特性的功能表面，将对各种科学发展产生重大影响，如传感器、微流体装置、可控药物输送、光学数据存储、自清洁、防雾和防污表面。光作为一种刺激可以提供远程控制传感器响应的能力，具有高速度和空间精度。测量和量化参与光响应聚合物表面的界面力将有助于阐明响应材料中粘附的起源。随着光致运动在分子水平上的研究，对聚合物的理解，特别是在二维空间中的理解将得到改善。这个项目的技术性质为研究生和本科生在聚合物合成和薄膜表征方面提供了跨学科的培训经验。该培训将为学生提供解决聚合物科学家未来需求所需的技能。该提案的一个重要外展组成部分包括？夏令营?为10名高中教师举办的活动，旨在为教师提供在课堂上进行的涉及聚合物科学的简单实验。这项外展项目的最终目标是通过影响年轻学生从事科学和工程职业，产生巨大的社会和经济影响。

TECHNICAL SUMMARY: This proposal outlines a 5 year plan centered on understanding how light-induced conformation changes in surface-bound polymer brushes influence surface, interfacial, and macroscopic properties in photochromic thin films. The three dimensional arrangement of photochromic moieties in extended polymer chains result in an increased density of functional groups at the surface that can be used to amplify the stimuli responsive nature of functional coatings. This proposal is aimed at synthesizing photochromic polymer brushes using surface initiated polymerization techniques that can be used to complete the following three research objectives: (1) Using light to control the colorimetric response of photochromic polymers through metal ion complexation. The reversible binding mechanism of photo-induced complexation that occurs when spiropyran containing polymers are irradiated in the presence of different metal ions will be elucidated and exploited to generate reversible ion sensors. (2) Investigating reversible, photo-switchable adhesion. The design of surfaces that undergo photo-induced phase separation will allow for surfaces that switch from adhesive to non-adhesive states. (3) Investigating photo-induced mechanical motion on the single molecule level. Light will be used to induce conformation changes between random coils and extended chains on surface of different free energy, leading to photo-induced mechanical motion.NON-TECHNICAL SUMMARY: The creation of functional surfaces with controlled interfacial properties using light as an external stimulus will have a major impact on a wide variety of scientific developments, such as sensors, microfluidic devices, controllable drug delivery, optical data storage, self-cleaning, antifogging and antifouling surfaces. Light as a stimulus can provide the ability to control sensor response remotely, with high speed and spatial precision. Measuring and quantifying the interfacial forces involved in photoresponsive polymer surfaces will help to elucidate the origins of adhesion in responsive materials. The understanding of polymers, especially in two-dimensional space, will be improved with the investigation of photo-induced motion at the molecular level. The technical nature of this project provides an interdisciplinary training experience to graduate and undergraduate students in polymer synthesis and thin film characterization. This training will provide students with the skill set necessary in addressing the future needs of polymer scientists. A significant outreach component of this proposal includes a ?summer camp? for ten high school teachers to be held at the University of Georgia is aimed at providing teachers with simple experiments involving polymer science to perform in their classrooms. The ultimate goal of this outreach project is to provide a large social and economic impact by influencing young students to pursue careers in science and engineering.